This past week, Moshe Katzav was found guilty in the Israeli court system of terrible crimes. This is a horrible chilul Hashem because he is seen by many as a religious person. Since the public does not know all the facts and testimony of the case, are we to believe the decision of the court? Should Moshe Katzav be known, beyond the shadow of a doubt, as a rapist or is there room to be dan lekaf z’chut even after the court rendered its decision? If there is room to be dan lekaf z’chut, doesn’t that undermine the judicial system? A system a civilized society cannot live without?
If the decision of a secular court is a credible according to Torah law is a question which should be posed to a prominent Dayan who is fully fluent in all the Halachic aspects of testimony and accepting evidence. Rav Yaacov Ariel Shlit"a in the Hebrew counterpart of this website has already dealt with part of these issues. At any rate, Moshe Katzav plans appealing the courts decision so there is nothing to be said until that time as far as what the final verdict will be. If the media and public opinion has influence the court's decision is not an issue of Halachic nature but we should all pray that truth shall prevail. Indeed the stumbling of a public figure is a Chilul Hashem. The Rambam (רמב"ם הלכות תלמוד תורה פרק ז הלכה א) discusses how public figures should be punished. From the Lashon Hara perspective, different Halachot apply when a person sins against a fellow man and when one sins against Hashem. See Chafetz Chaim (Klal 4 and Klal 10). All the Halachot discussed by the Chafetz Chaim are in regard to when Lashon may be spoken when a Jew harms another are in cases when are talking may have an effect to prevent further harm to another. This aspect is not in our hands but in the hands of the court, therefore I will deal with your question from the perspective of one sinning against Hashem. The Chafetz Chaim differentiates between different types of people who sin against Hashem. An observant Jew who normally does not sin on purpose, an observant Jew who possibly may sin on purpose, an observant Jew who definitely sins on purpose, and a Tzadik. Also discussed are by the Chafetz Chaim are a Rasha, an already proven Rasha etc. In some of the former cases even if we have observed with our own eyes the person sinning will still must give the benefit of the doubt. If the facts suggest that it indeed was deliberate we are not required to judge him Lechaf Zechut but it is still preferable. If the sin was definitely done on purpose and he accepts criticism it is still forbidden to embarrass this person in public. One must try to influence privately to change his ways. There are many more details to be studied all in the Chafetz Chaim (as quoted above) . But what we do see that there are certain situations that even if one definitely sinned one must still judge him to kaf Zechut or it is at least praiseworthy. May Hashem inform us Besorot Tovot and keep us safe from "nisayon and bizayon"as is said in the Tefilla.